The aim of this invention is to provide an aircraft that has higher chance of surviving attacks from anti-aircraft weapons when flying over enemy territory than aircraft currently in use. The aircraft according to this invention is fitted with a mechanism that enables the aircraft to travel in a continuous spiralling motion while flying over enemy teritorry, without the need for the pilot to make continuous control adjustments. The mechanism is such that once activated, the spiralling motion is automatic. The mechanism can aslo be dis-engaged by the pilot when so desired. The spiralling motion is achieved during flight without rolling the aircraft.
While a pilot flying a conventional aircraft such as a jet fighter could make the conventional aircraft fly in a spiralling motion, this could only be achieved if the pilot kept making continuous control changes with his own arm. This could become quite tiresome and strenuous after a while and would require continued concentration, if the spiralling was achieved without rolling the aircraft. Rolling the aircraft, as in the form of a barrel roll, may seem like an easy alternative, but continuous rolling would make the pilot dizzy after a while, leading to loss of control, and if close to the ground, a potential for a crash. A continuous rolling motion would also make it hard for the pilot to observe enemy territory, navigate and make target selection. That is, using a sustained rolling motion in order to achieve a prolonged spiralling motion would not be practical.
The aircraft in this invention would allow the pilot to operate conventional controls in a conventional manner, as when flying in a smooth manner, while the aircraft continued to travel in a spiralling motion. The advantage of this is that the pilot would be able to continue to observe enemy territory and would be free to concentrate on targeting enemy sites while the aircraft flew in an evasive manner.
In this invention the spiralling motion of a fast flying aircraft is achieved using moveable fins on a rotatable tube, with the tube encircling a part of the aircraft (preferrably the front area of the aircraft) and able to rotate around the encircled part of the aircraft. Fitted to an aircraft that is in the form of a jet propelled aeroplane, the rotatable tube would preferrably be fitted so as to encircle part of the fuselage.
The fins are attached to the rotatable tube so that they can be rotated in a pivoting manner relative to the rotatable tube. That is, if the rotatable tube was kept in a fixed position on the aircraft so as not to rotate, the fin movement would resemble the movement of canards on aircraft such as the Eurofighter and the recent version of the Sukhoi Su-31. The fins would turn in a pitch altering motion in the same direction. With the fins horizontal, the aircraft would be able to fly smoothly. When the fins are rotated from the horizontal position, they would act to push the aircraft in a similar manner to the way that canards would (if positioned on the front of the aircraft).
For the aircraft to enter a spiralling motion, the fins would need to revolve around the body of the aircraft so that the aircraft is pushed in changing directions. In the invention this is achieved by using the rotatable tube, that allows the fins to revolve around the body of the aircraftxe2x80x94using the rotatable tube as means of travelling around a part of the body of the aircraft. The invention provides a number of means by which rotation of the rotatable tube can be achieved. One way is to use fins that are of unequal size with respect to one another. Having fins that are of unequal size would cause an aerodynamic imbalance when the fins are moved from the horizontal position. With one fin pushing harder than the other, rotation of rotatable tube would result. The rotation of the rotatable tube would be automatic and continuous while the imbalance between the fins was maintained. Placing the fins back in a horizontal position would remove the imbalance, allowing the rotatable tube to come to rest. Friction between the aircraft and the rotatable tube or a braking mechanism such as a hydraulicly activated brake pad being push against the rotatable tube could help to stop the rotatable tube from rotating.
Another way of causing the rotatable tube to rotate according to the invention is to increase the pitch of one fin more than that of the other. Increasing the pitch of one fin relative to the other would cause an aerodynamic imbalance on the rotatable tube, thereby forcing it to rotate. Allowing the fins to return to a horizontal position would remove the aerodynamic imbalance, allowing the rotatable tube to come to rest.
Although the aircraft could be in the form of a jet propelled aeroplane, it could be in the form of any one of a range of aircraft such as guided missiles and unguided missiles. It could also be in the form of un-propelled aircraft such as gliders or winged bombs that are designed to glide to a target.